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1.
Phys Chem Chem Phys ; 19(8): 6022-6029, 2017 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-28184405

RESUMEN

The focus of this work is on addressing how the adsorption properties of cyclodextrin (CD) based polymeric hydrogels (cyclodextrin nanosponges, CDNS) can be regulated by a precise control of a crucial parameter such as the characteristic pore size of the polymer network. With this aim, Small Angle Neutron Scattering (SANS) experiments are performed on different CDNS polymer formulations, differing by (i) the chemical structure of the cross-linking agent used for the polymerization of CD, which affects the flexibility of the strands between two crosslinking junctions, (ii) the relative molar ratio of cross-linker to monomer, affecting the cross-linking density, and (iii) the dimension of the CD macrocycle, regulating the steric hindrance and number of available reactive sites on the monomer. The analysis of the experimental data in terms of a two-correlation-length model allows one to extract a correlation length ζ that is interpreted as an experimental assessment of the average mesh-size of the cross-linked polymer, confirming the effective nano-size of the cavities formed in the network of CDNS. The hydration-dependence of ζ is modelled by an empirical functional form, that provides as key parameters the swelling rate of the polymeric network and the upper limit for the mesh size of the material. These parameters are useful for the characterization of the dynamic response of the hydrogel to swelling and the maximum mesh size compatible with the chemical structure of the polymer.

2.
Soft Matter ; 12(43): 8861-8868, 2016 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-27734051

RESUMEN

The focus of the present work is to shed light on possible modifications of the molecular properties of polysaccharide hydrogels induced by the establishment of specific non-covalent interactions during the loading of a guest compound inside the gel phase. With this aim, a case study of the encapsulation of caffeine (Caf) inside cyclodextrin-based hydrogels, namely, cyclodextrin nanosponges (NS), is systematically investigated here by using UV Raman scattering experiments. The UV Raman spectra of the hydrogels, analysed as a function of temperature, concentration of the guest molecule loaded in the gel phase and pH, prove particularly informative both on the structural rearrangements of the hydrophobic/hydrophilic groups of the polymeric network and on the breaking/formation of specific guest-matrix interactions. Analysis of the temperature dependence of dynamical parameters, i.e., the dephasing time associated with specific vibrational modes of the polymer backbone, enables the proposal of a molecular picture in which the loading of Caf in NS hydrogels tends to favour access of the water solvent to the more hydrophobic portions of the polymer matrix, which is in turn reflected in a marked increase in the solvation of the whole system. The achievements of this work appear of interest with respect to the design of new possible strategies for controlling the diffusion/release of bioactive molecules inside hydrogel networks, besides corroborating the potential of UV Raman scattering experiments to give new molecular insights into complex phenomena affecting hydrogel phases.

3.
Phys Chem Chem Phys ; 18(17): 12252-9, 2016 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-27081681

RESUMEN

The fundamental question of how the reorganization of the hydrogen-bond (HB) network of water is influenced by the combination of nano-confinement and hydrophobic/hydrophilic solvation effects is addressed here using a spectroscopic study of water absorbed in a model, pH-sensitive polysaccharide hydrogel. The effects of temperature, hydration level and pH on the vibrational dynamics associated with the water molecules and the polymer skeleton are disentangled and analysed by a complementary and combined use of UV-Raman scattering and IR spectroscopy. The experimental data give evidence that the solvation effects in the hydrogel matrix are essentially dominated by the hydration of more hydrophobic parts of the polymer network, while the effect of pH on the HB reorganization of confined water molecules is found to be similar to that induced by cooling of the system. A tentative explanation of these results has been provided in terms of interplay between different kinds of interactions, i.e. hydrophobic vs. hydrophilic.

4.
Phys Chem Chem Phys ; 17(2): 963-71, 2015 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-25407481

RESUMEN

The molecular dynamics of water and a polymer matrix is here explored in a paradigmatic model of a polysaccharide hydrogel, by the combined use of UV Raman scattering and infrared measurements. The case example of cyclodextrin nanosponges (CDNS)/hydrogel is chosen since the simultaneous presence in the structure of the polymer matrix of both hydrophilic and hydrophobic sites mimics the complexity of polysaccharide hydrogels. In this way, the contributions provided by the balance between the hydrophilicity/hydrophobicity and the grade of entanglement of the polymer hydrogel to lead to the formation of the gel phase are separately accounted and evaluated. As main results, we found that the hydrophobic CH groups inserted on the aromatic ring of CDNS experience a more pronounced dynamic perturbation with respect to the carbonyl groups due to the collision between the solvent and vibrating atoms of the polymer. The overall results provide a detailed molecular picture of the swelling phenomena occurring when a chemically cross-linked polymer contacts with water or biological fluids and exploits the potentiality of UV Raman spectroscopy to retrieve dynamic information besides their structural counterpart obtained by the classical analysis of the basic features of vibrational spectra.

5.
Phys Chem Chem Phys ; 17(15): 10274-82, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25798878

RESUMEN

A detailed experimental and theoretical vibrational analysis of hydrogels of ß-cyclodextrin nanosponges (ß-CDNS), obtained by polymerization of ß-cyclodextrin (ß-CD) with the cross-linking agent ethylenediaminetetraacetic acid (EDTA), is reported here. Thorough structural characterization is achieved by exploiting the complementary selection rules of FTIR-ATR and Raman spectroscopies and by supporting the spectral assignments by DFT calculations of the spectral profiles. The combined analysis of the FTIR-ATR spectra of the polymers hydrated with H2O and D2O allowed us to isolate the HOH bending of water molecules not involved in symmetrical, tetrahedral environments. The analysis of the HOH bending mode was carried out as a function of temperature, showing the existence of a supercooled state of the water molecules. The highest level of cooperativity of the hydrogen bond scheme was reached at a value of the ß-CD/EDTA molar ratio n = 6. Finally, the connectivity pattern of "uncoupled" water molecules bound to the nanosponge backbone was found to be weakened by increasing T. The temperature above which the population of non-tetracoordinated water molecules becomes predominant turned out to be independent of the parameter n.

6.
J Chem Phys ; 142(1): 014901, 2015 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-25573577

RESUMEN

The molecular connectivity and the extent of hydrogen-bond patterns of water molecules confined in the polymer hydrogels, namely, cyclodextrin nanosponge hydrogels, are here investigated by using vibrational spectroscopy experiments. The proposed spectroscopic method exploits the combined analysis of the vibrational spectra of polymers hydrated with water and deuterated water, which allows us to separate and selectively investigate the temperature-evolution of the HOH bending mode of engaged water molecules and of the vibrational modes assigned to specific chemical groups of the polymer matrix involved in the physical interactions with water. As main results, we find a strong experimental evidence of a liquid-like behaviour of water molecules confined in the nano-cavities of hydrogel and we observe a characteristic destructuring effect on the hydrogen-bonds network of confined water induced by thermal motion. More interestingly, the extent of this temperature-disruptive effect is found to be selectively triggered by the cross-linking degree of the hydrogel matrix. These results give a more clear picture of the molecular mechanism of water confinement in the pores of nanosponge hydrogel and open the possibility to exploit the spectroscopic method here proposed as investigating tools for water-retaining soft materials.


Asunto(s)
Hidrogeles/química , Polímeros/química , Agua/química , Ciclodextrinas/química , Enlace de Hidrógeno , Nanoestructuras/química , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Temperatura
7.
Jpn J Radiol ; 42(4): 354-366, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37987880

RESUMEN

Squamous cervical carcinoma (SCC) requires particular attention in diagnostic and clinical management. New diagnostic tools, such as (positron emission tomography-magnetic resonance imaging) PET-MRI, consent to ameliorate clinical staging accuracy. The availability of new technologies in radiation therapy permits to deliver higher dose lowering toxicities. In this clinical scenario, new surgical concepts could aid in general management. Lastly, new targeted therapies and immunotherapy will have more room in this setting. The aim of this narrative review is to focus both on clinical management and new therapies in the precision radiotherapy era.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias del Cuello Uterino , Femenino , Humanos , Tomografía de Emisión de Positrones , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/radioterapia , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Quimioradioterapia/métodos , Estadificación de Neoplasias
8.
Eur Rev Med Pharmacol Sci ; 25(10): 3647-3654, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34109573

RESUMEN

OBJECTIVE: Approximately 50% of cancer patients develop bone metastases in their natural disease history. The management of metastatic bone disease requires a multidisciplinary approach. Both radiofrequency ablation (RFA) and radiation therapy (RT) were safe and effective in the management of painful metastases, even if they rely on totally different action mechanisms. A synergistic combination of RT and RFA seems to result in a better pain control. A systematic review was performed to describe the feasibility and effectiveness of the association between RFA and RT in the treatment of metastatic bone pain in oligo-metastatic patients, evaluating its role in alleviating bone pain, reducing the risk of fractures, and consequently ensuring a better quality of life. MATERIALS AND METHODS: A systematic database search was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This systematic review included studies that reported populations meeting the following inclusion criteria: (I) confirmed bone metastases in adult patients; (II) active bone metastases pain; (III) patients treated with combined RFA-RT; (IV) Original studies. RESULTS: Three papers that evaluated the combined treatment with doses ranging from moderately hypofractionated three-dimensional conformal RT (3D-CRT) and stereotactic body radiation therapy (SBRT) schedules were selected. CONCLUSIONS: The RFA-RT combined strategy appears to be promising in terms of efficiency and safety with adequate pain control and quality of life improvement. Positive effects on time to local failure and overall survival increase were also observed. Further prospective studies are needed to better delineate RFA-RT treatment benefits.


Asunto(s)
Neoplasias Óseas/terapia , Hipofraccionamiento de la Dosis de Radiación , Ablación por Radiofrecuencia , Radiocirugia , Neoplasias Óseas/secundario , Dolor en Cáncer/terapia , Terapia Combinada , Fracturas Óseas/prevención & control , Humanos
9.
Eur Rev Med Pharmacol Sci ; 25(4): 1821-1827, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33660791

RESUMEN

OBJECTIVE: Paget disease of the breast (PDB) is a rare form of cutaneous breast cancer. Up to date, no randomized studies evaluated the different management strategies. This systematic review investigates the role of radiotherapy and its best technical profile in the treatment of this disease, with great attention to doses and fractionation regimens. MATERIALS AND METHODS: A systematic search was performed on PubMed, Embase and Scopus in order to detect case reports, case series and prospective as well as retrospective clinical studies describing histologically proven PDB and providing information about pertinent radiation treatments. Searching strategy followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines. RESULTS: Inclusion criteria were met by six papers, dealing with radiation treatments performed postoperatively and in exclusive settings. No evaluations were performed on preoperative radiotherapy. CONCLUSIONS: Actually, the standard treatment of PDB reflects oncological principles of breast carcinoma therapy, including the role of breast-preserving surgery. The traditional radiotherapic dose is 50 Gy, with daily fractionation of 2 Gy. Adjuvant radiotherapy following breast preserving surgery represents the current standard of care; prospective studies could be of help in defining the role of exclusive radiotherapy, hypofractionated schemes and smaller target volumes.


Asunto(s)
Enfermedad de Paget Mamaria/radioterapia , Femenino , Humanos , Enfermedad de Paget Mamaria/cirugía , Radioterapia Adyuvante
10.
J Pharm Biomed Anal ; 47(4-5): 704-9, 2008 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-18400444

RESUMEN

In this work, the usefulness of (2-hydroxypropyl)-beta-cyclodextrin (HP-beta-CyD) as a tool to form an inclusion complex with 9-fluorenonic derivative (AG11) has been investigated, in pure water, by UV absorption. Phase-solubility diagrams allowed the determination of the association constant between AG11 and HP-beta-CyD. At the same time, solid binary systems between AG11 and HP-beta-CyD have been prepared in 1:1 stoichiometry by co-precipitation method. In order to confirm the complexation, FTIR spectroscopy in ATR geometry measurements have been performed and the results have been compared with the free compounds and the corresponding physical mixture in the same molar ratio. The nature of the interactions between AG11 and HP-beta-CyD has been elucidated also by applying mathematical procedures such as deconvolution and curve fitting. Improvement of the aqueous solubility is expected to improve the bioavailability of the drug in oral administration.


Asunto(s)
Fluorenos/química , Espectrofotometría Ultravioleta/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Estructura Molecular , Transición de Fase , Solubilidad , Agua/química
11.
Sci Rep ; 8(1): 6105, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29666447

RESUMEN

Invertebrates represent the most plentiful component of marine biodiversity. To date, only few species have been documented for marine litter intake. Here, we report for the first time the presence of macroplastic debris in a jellyfish species. Such novel target to plastic pollution highlights an under studied vector of marine litter along marine trophic web, raising further concern over the impact on marine wildlife.


Asunto(s)
Plásticos , Conducta Predatoria , Escifozoos/fisiología , Contaminantes del Agua , Animales , Ingestión de Alimentos , Monitoreo del Ambiente , Cadena Alimentaria , Plásticos/efectos adversos , Contaminantes del Agua/efectos adversos
12.
J Pharm Biomed Anal ; 44(1): 110-7, 2007 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-17379467

RESUMEN

The effect of beta-cyclodextrin (beta-CyD), (2-hydroxypropyl)-beta-cyclodextrin (HP-beta-CyD) and methyl-beta-cyclodextrin (Me-beta-CyD) complexation on the UV absorption of genistein (Gen) was studied in pure water. A phase solubility study was performed, according to the method reported by Higuchi and Connors, to evaluate the changes of isoflavone in the complexation state and the obtained diagrams suggested that it forms complexes with a stoichiometry of 1:1. Then, the solid complexes of genistein with these macrocycles in 1:1 molar ratio were prepared by the co-precipitation method and characterized by FTIR absorption spectroscopy in ATR geometry. The host-guest interactions have been evidenced by monitoring, in the FTIR-ATR spectra, the changes in some guest molecule bands relative to those observed in the spectra of the 1:1 physical mixtures and complexes. In particular, for the high-frequency O-H stretching band, a quantitative vibrational assignment of the observed sub-bands has been made. From the results, the inclusion phenomena have been discussed.


Asunto(s)
Antineoplásicos/química , Genisteína/química , Espectrofotometría Ultravioleta/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , beta-Ciclodextrinas/química , Estructura Molecular , Solubilidad , Temperatura de Transición , Agua/química
13.
G Ital Med Lav Ergon ; 29(3 Suppl): 639-40, 2007.
Artículo en Italiano | MEDLINE | ID: mdl-18409881

RESUMEN

Pleural malign mesothelioma is the only one to which we can straight attribute to an exposition, in professional and ambient ambit, to a good identified agent and, precisely, to the fibres of asbestos. Objective of our work has been to verify the incidence of the pleural malign mesothelioma in Sicily and in particular in the Messina's area, during the period 1988-2005. We have examined the epidemiologic data of the period 1988-1997 and 1998-2005 through the consultation of the Mesothelioma Sicilian Register; Mesothelioma Italian Register and of the available documentation in the Health Superior Institute. The study showed that the pleural malign mesothelioma in sicily and in Messina's area is reduced for the elimination of the asbestos and for the low use of asbestos in the sicilian industry.


Asunto(s)
Amianto/efectos adversos , Mesotelioma/epidemiología , Neoplasias Pleurales/epidemiología , Femenino , Humanos , Incidencia , Italia , Masculino
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(6 Pt 1): 061504, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16485952

RESUMEN

With the aim to investigate, by means of elastic neutron scattering, the effects produced by the cation substitution on the dynamics of water in zeolites, we measured, using a neutron backscattering spectrometer, the temperature dependence of mean-square atomic displacements [u2] derived from window integrated quasielastic spectra of fully and partially hydrated Na-A and Mg50-A zeolites. The results, collected in the 20-273 K temperature range, reveal that, at low temperature, the [u2] shows a harmonic trend independent of hydration and cation substitution, and, at higher temperatures, the onset of a non-Gaussian dynamics of the elastic intensity. This latter takes place at T approximately 200 K and approximately 150 K for fully and partially hydrated samples, respectively. This behavior has been interpreted in terms of reorientational jumps of H atoms described by two-site processes within an asymmetric double-minimum potential. In spite of its simplicity, the model seems to reproduce the rearrangement of the hydrogen bond network of zeolitic water. The fit results indicate a reduced proton mobility by diminishing the water content and by the induced Na+-->Mg2+ ion exchange, in agreement with previous incoherent quasielastic neutron scattering results at higher temperatures.

16.
Eur Phys J E Soft Matter ; 12 Suppl 1: S55-8, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15011016

RESUMEN

We performed, in the O-H stretching region, Fourier-transform Infrared (FT-IR) Absorption measurements for investigating the vibrational dynamics on water confined in NaA zeolite, vs. temperature and for different hydration percentages. The spectral substructure of the O-H stretching band is explained postulating the existence of three major components centred at approximately 3290 cm(-1) (omega(1)), approximately 3470 cm(-1) (omega(2)), approximately 3590 cm(-1) (omega(3)), with different dynamical properties traced over the full T-range investigated.

17.
J Pharm Biomed Anal ; 29(6): 1149-52, 2002 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12110401

RESUMEN

In the present work we report a Fourier Transform Infrared (FT-IR) analysis performed on rat encephalon samples in the CH-OH vibrational stretching region (2400-3800) cm(-1), in order to reveal the presence of a very diffuse commercial benzodiazepine: VALIUM. The comparison between the spectral features of normal brain and the ones of samples with administrated substance has unambiguously showed that the CH stretching region seems not to suffer from any change for the pharmacological treatment, instead the OH band is strongly modified probably due to the presence of a new spectral contribution characteristic of diazepam molecule.


Asunto(s)
Benzodiazepinas/análisis , Química Encefálica , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Animales , Técnicas In Vitro , Masculino , Ratas
18.
G Chir ; 23(1-2): 43-4, 2002.
Artículo en Italiano | MEDLINE | ID: mdl-12043470

RESUMEN

The case of a 57-year-old man with three synchronous malignancies of the lung (adenocarcinoma, small cell carcinoma, squamous carcinoma in situ) is presented. This is one of the few cases reported in the literature with three different histologic types in the same pulmonary lobe.


Asunto(s)
Adenocarcinoma/diagnóstico , Carcinoma in Situ/diagnóstico , Carcinoma de Células Pequeñas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias Primarias Múltiples/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
19.
G Chir ; 13(6-7): 363-5, 1992.
Artículo en Italiano | MEDLINE | ID: mdl-1382531

RESUMEN

The authors report a case of macroamylasaemia and discuss diagnostic implications especially in surgical emergencies. In fact, laboratory findings of hyperamylasaemia may lead to erroneus diagnosis or even to useless surgical operations.


Asunto(s)
Amilasas/sangre , Diagnóstico Diferencial , Humanos , Sustancias Macromoleculares , Masculino , Persona de Mediana Edad
20.
G Chir ; 14(3): 173-5, 1993 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-8518083

RESUMEN

Muscular localization of echinococcosis is considered unusual. The authors report a case of such uncommon hydatid localization. Pathogenetic hypotheses are discussed.


Asunto(s)
Equinococosis/diagnóstico , Enfermedades Musculares/diagnóstico , Adulto , Equinococosis/etiología , Equinococosis/cirugía , Humanos , Región Lumbosacra , Masculino , Enfermedades Musculares/etiología , Enfermedades Musculares/cirugía
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